net: qualcomm: rmnet: Dl marker v2 callbacks

Modify the callbacks for Dl marker so that they can
handle new qcmd field in dl marker v2 variant of.
Accompanying rmnet modules will now
register to the v2 callback interface variant.

Change-Id: Ic242b2cdd9048f77864d514a846160aa08506de6
Signed-off-by: Conner Huff <chuff@codeaurora.org>